Pactia — Cursor / VS Code extension
Syntax highlighting for .pactia files and ```pactia fences in Markdown — Pactia spec 1.2.
Spec: language-spec | editor-support | registry | CHANGELOG
Install
git clone https://github.com/pactia-lang/vscode-pactia.git
cd vscode-pactia
./scripts/install-extension.sh
Targets Cursor and VS Code when present. Options: --cursor or --vscode only.
In a pactia-lang monorepo checkout, run ./vscode-pactia/scripts/install-extension.sh from the repo root instead.
Then Developer: Reload Window — language mode must be Pactia on .pactia files. In Markdown, open a ```pactia fence to confirm highlighting.
Development
cd vscode-pactia
npm install
npm test # full suite (extension, scopes, fixtures, markdown)
npm run test:scopes # declarative scope contract cases
npm run test:fixtures # scan spec/examples fixtures for balance + scopes
npm run package # pactia-<version>.vsix
npm run install:extension
Markdown fences
With the extension installed, ```pactia blocks in .md files get full Pactia highlighting (including spec/docs/). Use the pactia fence tag — not rust or plain text.
```pactia
pactia 1.0
product MyApp {
> Agent rules and product context.
}
```
GitHub.com does not highlight pactia fences until Linguist adds the language; local preview relies on this extension.
Grammar tests use vendored copies under testdata/fixtures/, with fallbacks to pactiac test/fixtures in a monorepo layout.
testdata/fixtures/context/context-example.pactia — context blocks, export, attach, aliastestdata/fixtures/kernel/fleet-management-v2.pactia — kernel product reference (synced from pactiac relay.pactia)testdata/fixtures/packages/fintech-rules-index.pactia — package export def @ / export def #testdata/fixtures/single-file/fleet-management-v2.pactia — single-file layout
Token colors (built-in)
Default colors for .pactia files (dark themes):
| Element |
Color |
Scope |
Clause tags @actor, @api |
Yellow, bold (@ + tag name) |
entity.name.tag.clause.pactia |
Modifier tags @@output, @@pk |
Yellow, bold (@@ + name) |
entity.name.tag.modifier.pactia |
Tag targets customers, Vehicle |
Theme default |
entity.name.tag.target.pactia |
Macros #list, #[list] (legacy) |
Theme default (Rust-like) |
entity.name.function.macro.pactia |
Prose > lines |
Purple, italic |
string.unquoted.prose.pactia |
Prose > prefix |
Green |
punctuation.definition.prose.quote.pactia |
| Kernel keywords |
Blue |
keyword.declaration.pactia |
Def sigils / imports @, @@, #, from |
Blue |
punctuation.definition.def-sigil.pactia, keyword.control.import.pactia |
Placement / def spec in service, modifier, |
Gold |
constant.language.placement.pactia, constant.language.def-spec.pactia |
HTTP GET/POST |
Yellow |
keyword.control.http.pactia |
Braces { } |
Gold |
punctuation.section.*.pactia |
Reload after updating (Developer: Reload Window). Confirm language mode is Pactia in the status bar.
Grammar coverage (spec 1.2)
| Construct |
Examples |
| Kernel keywords |
pactia, product, module, service, model, context, import, export, def, in |
| Three line kinds |
@tag { }, @@modifier, #macro, > prose |
| Clause tags |
@entity Vehicle { }, @api list { }, @auth Customer |
| Modifier tags |
@@output VehicleDto, @@pk, @@nullable (standalone field lines and inline) |
| Modifier flags |
@pk, @public, @pii, @optional |
| Modifier shorthand |
@output VehicleDto, @status 201, @emit vehicle.created |
| Macros |
#list, #rate_limit(1000, rpm), legacy #[list] |
| Package imports |
import @scope/name;, import { @api, @@output, #database } from @pkg; |
| Attach syntax |
module(catalog) { service(CatalogService) { model(catalog_model) } }, context(api_notes) |
| Context blocks |
context api_notes { path: "docs/api.md" }, export context …, def alias = context api_notes { } |
| export def |
export def @name in service { }, export def @@name in field { }, export def #name in service { } |
| Module constants |
def max_page = 100 |
| Prose / interpolation |
> line, >> block >>, ${max_page} |
| Inline objects |
{ service: FleetService, metric: error_rate } |
Not highlighted as kernel keywords
- Macro/tag/modifier names (
list, output, auth, …) — scoped as tag/macro entities, not keywords
on, when, then in prose — plain text unless inside structured tag fields
Keeping grammar in sync
- Update pactia-lang/spec docs and fixtures
- Refresh
testdata/fixtures/ when pactiac canonical fixtures change
- Edit
syntaxes/pactia.tmLanguage.json (and pactia.markdown.tmLanguage.json if fence behavior changes)
- Run
npm test
- Run
npm run install:extension and reload window
Roadmap
| Version |
Feature |
| 1.3.0 |
context keyword — blocks, export, attach, module alias |
| 1.2.0 |
Spec 1.2 grammar — def @/@@/#, attach syntax, partial imports, #macro invoke |
| 1.0.2 |
Clause tag colors, single-line @stack, comprehensive grammar tests |
| 1.0.1 |
Markdown ```pactia fence injection |
| 1.0 |
Spec 1.0 grammar — registry blocks, qualified imports, package authoring |
| 1.x |
Snippets for service, @api, @test |
| 2.0 |
LSP — tag/macro completion from workspace registry |
| |
